bnjie, The BIOS battery in located on the motherboard of the server. It's about the size of a quarter. After replacing it you will need to load the default BIOS settings by following these steps: Connect a USB Keyboard to the fixture Power ON the Fixture When the media server is turned ON, repeatedly press the ‘DEL’ or ‘DELETE’ button on the USB Keyboard. This will open the BIOS Settings. Using the Arrow Keys, go to the ‘Save and Exit’ Menu Option at the top. Go to the ‘Load Default’ and press ENTER. Confirm. Go to Save and Exit. Confirm again.